Turret gun directing system (aideye)



July 29, 1969 H. M. SUMRALL 3,457,827

TURRET GUN DIRECTING SYSTEM (AIDEYE) Filed May .5, 1968 2 Sheets-Sheet 1 -L 53 32 54 s I /40 37 '39 '9 52 JR-i 22 25 I/\"V1.N'/(}R 32 U HOWELL M. SUMRALL C m ROY MILLER ATTORNEY.

GERALD F. BAKER AGENT.

July 29, 1969 H. M. SUMRALL. 3,457,827

' TURRET GUN DIRECTING SYSTEM (AIDEYE) Filed ma 5, 1968 2 Sheets-Sheet 2 All FIG. 6.

United States Patent 01 fice US. CI. 89-41 2 Claims ABSTRACT OF THE DISCLOSURE An apparatus is provided for sensing infrared radiation from a distant point, thus determining the direction of a target at which a turret gun may fire and for causing the gun to be automatically directed at that point.

Background of the invention Low flying aircraft have become increasingly vulnerable to ground fire. One reason for this is because of the increased accuracy of surface-to-air missiles. Retaliation on the other hand is diflicult. A serious limitation lies in the fact that gun fire must be within a few degrees of the point of focus to be detected visually unless continuous firing is being conducted or the lookout happens to be looking at the source in the case of sporadic or single shot firing. In the case of rifie fire, it is possible for the rifleman ot take a shot, move his position, and fire again without being detected. With each firing he increases the probability of scoring a damaging hit.

The probability of spotting a target of the type discussed could be greatly improved by means of infrared detection devices. Accordingly, I have designed the disclosed infrared detection device for use with conventional turret gun directing systems.

Summary of the invention The detector according to the present invention, which I have named AIDEYE, employs a hemispherically shaped grid comprising plural rows of locator pins which may be caused to project into the inner side of the hemisphere. The actuation of one of the solenoids on a detector arm, by the infrared detector unit on said arm, raises at least one of the pins into the path of a rotating sweep arm inside the hemisphere. When the progress of the sweep arm is impeded by a pin, strain operated switches cause power to be supplied to the'turret gun directing system to bring the gun to a position corresponding to the position of the protruding pin. 'It is contemplated that the system be so compensated that, within ordinary ranges of speed of the aircraft, positioning of the gun would be within plus or minus one degree of the target.

Brief description of the drawing FIG. 1 is a perspective view of a portion of an airframe mounting a conventional gun turret and a sensor device according to the present invention;

FIG. 2 is a detailed diametral cross sectional view of the sensing device of FIG. 1;

FIG. 3 is a detail view taken in the area indicated by arrow 3 in FIG. 2;

FIG. 4 is a cross sectional view taken along the line 44 of FIG. 2;

FIG. 5 is a detail view, partly in cross section, taken along line 55 of FIG. 2; and

FIG. 6 is a cross sectional view taken along line 6-6 of FIG. 3.

Detailed description of the invention Referring to FIG. 1, I will first generally describe component parts of the gun turret and so much of the sta- 3,457,827 Patented July 29, 1969 bilizing and control apparatus as may be necessary to an understanding of the cooperation therewith of the infrared radiation sensing mechanism of the present invention. The gun turret, which is conventional, is represented generally at 11 and is shown rotatably mounted upon supports 13, constituting, for example, a part of 01 fastened to the frame 60 of an aircraft. To one of these supports 13 is secured an internally toothed gear 34 adapted to mesh with a pinion 15 driven by motor 24 which is mounted in the turret for driving the turret in azimuth about the axis 26. Although I have illustrated various components of the present system in spaced relation for clearness, it will be understood that many of the parts, as hereinafter described, such as the drive motors 24, 24' and other gun control mechanisms are mounted in or on the turret for movement therewith both in azimuth and elevation. The inner shell of the turret is rotatably supported in the outer shell 20 to pivot about the axis 17 in elevation when driven by motor 24' through pinion 15.

The scanner mechanism according to the present invention is indicated generally at 10 and is shown in FIG. I mounted on the frame 60 forward of the turret 11. Scanner 10 comprises a rotatable detector mechanism 18 having an outer sweep arm 19 which will be more completely described with respect to FIGS. 2-6. The mechanism 18, except for outer sweep arm 19', is protected by a housing 30 comprising a flat top portion 36 and 9. depending hemispherical portion 32.

Turning now to FIG. 2 it may be seen that sweep arm 19 carries IR sensors 14 and is fixed to a shaft 29 which may be rotated at a relatively high speed through gears 12, 16 by means of a conventional stepping motor (not shown). The shaft 29 is rotatable inside a hollow shaft 21 which is journalled at one extremity in the housing member 32 and carries flie locator arm 25. Arm 25 is curved to fit the inner curvature of hemisphere 32 and is supported at one extremity by a straight portion 40. The hemisphere 32 carries slidable locator pins 35 which normally protrude externally of the housing'member 32. One of the locator pins, designated as 38, has been shown protruding inside of member 32 and in the path of arm 25 as will be explained later. Shaft 21 is frictionally connected to hollow shaft 45 as by friction springs 62 and is normally driven thereby through gears 31, 33. Hollow shaft 45 is journalled in bushing 56 fixed in housing member 36 and. carries gear 33 on one end and gear 54 on the other. Gear 54 meshes with gear 52 and, as will be more fully described, rotates shaft 53 to move arm 22 when motion of arm 25 is impeded by an internally protruding pin such as is shown at 38. Arm 22 carries normally open contacts 37, 39 adapted to be closed when forward motion (i.e. to the right of arrow B) is impeded by pin 38. Normal rotation of shafts 29 and 21 is clockwise as shown by arrow A.

Further details of the locator arms and pins are shown in FIG. 3 wherein it will be noted that pins 35, 38 are maintained in one of two positions by means of detent balls 44 under pressure of springs 46. Ann 19 is shown partially broken away in longitudinal cross section to reveal solenoids 41 embedded therein which, when energized, effect movement of cores 42 against return springs 43 so that a pin 35 will thus be moved to the position indicated by pin 38. The arm 19 is composed of insulating material having a conductive coating 55 on two sides thereof as shown in FIG. 4.

FIG. 4 further reveals the connection of the solenoids 41 to the sensors 14 through the conductive coating 55. Although the connection may be made directly without amplification, the circuit shown in FIG. 4 includes a transistor 50. A conductor 47, connected to the positive potential of a source of intermittent DC. current is provided along the full length of the inner portion of arm 19 and the outer portion carries -a similar conductor 48 connected to the negative potential of the source. For convenience the conductive members, the transistors, the sensors and any other elements associated therewith may be plated on or imbedded in the material of arm 19.

The locator arms 22 and 25 are servo-connected to pinions 15 and 15 in any well known manner and may, for example, be connected in a manner similar to that described in US. Patent No. 2,968,997, issued Jan. 24, 1961 to G. C. Newton, In, et a1.

Regardless of the system used, it preferred that, when arm 25 is arrested by representative pin 38, the gun will be positioned in azimuth. Looking now at FIGS. 2 and it will be seen that, when movement of arm 25 is arrested by pin 38, rotation of shaft 21 will stop and continued rotation of gear 54 relative to shaft 21 will cause rotation of gear 52, shaft 53 and attached arm 22. Arm 22 will move in a counterclockwise direction as viewed in FIG. 2, until its progress is arrested also by pin 38. At this time the gun shall be pointing in the direction of a detected IR source. As torque continues to be applied to shaft 53 slippage occurs between the shaft 53 and arm 22, but sufficient strain is placed on arm 22 to cause the contacts 37, 39 to touch closing a circuit to an indicating means perceptible to the gun operator. Upon receipt of the signal, the gun operator then makes a decision as to the advisability of firing the gun at that target. Whether or not he decides to fire, he should immediately act to clear and reset the detector mechanism.

Reset is accomplished by simply reversing the rotation of gear 31 for a duration Sllfi'lCieIlt to accomplish a 365 rotation of arm 25 to ensure resetting of all pins protruding into the hemisphere 32. For this purpose the arm 25 is beveled as shown in FIG. 6, after one rotation of arm 25 to clear the locator mechanism, rotation in the clockwise direction is resumed at the will of the gun operator to seek another target.

The gun turret may be stabilized by a gyroscope in a well known manner and the system compensated for the average lag inherent therein to increase the accuracy of the mechanism. It is also contemplated that the system will be compensated for the average speed of the vehicle in order to eliminate errors inherent therein.

What is claimed is:

1. In a weapon directing system wherein the weapon is mounted on a support movable in azimuth and in elevation under control of servo-signalling from a director unit, improvement comprising:

(A) radiation responsive detector means including,

(1) a rotatable sweep arm describing a substantially hemispherical surface of revolution,

(2) a plurality of radiation responsive sensor means on said sweep arm, and

(3) a like plurality of electromechanical actuator 4 means on said sweep arm each responsive to a corresponding sensor means to effect a mechanical output when said corresponding sensor is afiected by radiation; (E) stop means including,

(1) a substantially hemispherical body member,

and

(2) a plurality of locator pins arranged in said body member normally protruding outwardly from said member and displaceable inwardly to a stop position by mechanical output from said actuator means on saidsweep arms;

(C) stop locator means including,

(1) first and second locator arms rotatably mounted in said body member such that any protruding locator pin will lie in the path of rotation of said first arm,

(2) drive means for driving said locator arms in azimuth and elevation respectively,

(3) said drive means including,

(a) first and second orthogonal shafts, and (b) frictional connecting means between said shafts and between said second shaft and said second arm so that (c) when said first arm encounters a protruding stop pin said second arm will be moved orthogonally to also contact said protruding stop pin; and (D) servo signalling means for detecting the positions of said arms and for directing said weapon to aim in a direction corresponding to the position of said pin. 2. The system according to claim 1 further comprising (A) signal means including (1) signal actuator means on said second arm,

and

(2) perceptual means available to a person assigned to said weapon for indicating final positioning of said weapon in said position corresponding to the position of said pin.

References Cited UNITED STATES PATENTS 2,237,193 4/1941 Mobsby.

3,147,384 9/1964 Fenton et al 25()83.3 x

FOREIGN PATENTS 246,861 4/1926 Italy.

BENJAMIN A. BORCHELT, Primary Examiner STEPHEN C. BENTLEY, Assistant Examiner US. Cl. X.R. 25083.3 

